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PubMedDate not supplied

Vascularity of the femoral head. Tc diphosphonate scintigraphy validated with tetracycline labeling.

99MTc diphosphonate scintigraphy and tetracycline labeling were performed on 22 hips in 20 patients in whom the femoral heads were subsequently removed. Twelve of the hips had acute neck fractures, and 10 hips had roentgenographic evidence of avascular necrosis. This technique is of greater value for recent fractures, for once revascularization begins to occur, increased radioactivity is usually found by scintiscan. There was good correlation between roentgenogram, scintiscan and tetracycline fluorescence. 99mTe diphosphonate scintigraphy, which can be performed outside the operating theater with little discomfort to the patient, proved to be a reliable, noninvasive method of assessing the blood flow to the femoral head. 99mTc diphosphonate scintigraphy is not a quantitative technique; it detects the presence or absence of femoral head blood flow, not the adequacy of that blood supply.

Adult↗

PubMed1996

Liposome-encapsulated dichloromethylene diphosphonate induces macrophage apoptosis in vivo and in vitro.

Dichloromethylene diphosphonate (MDPCl2) encapsulated in multilamellar liposomes was selectively incorporated by macrophages, immediately transferred to lysosomes, then released from liposomes into lysosomes by enzymatic digestion of the liposomal lipid layers. From 4 h after ingesting liposome-encapsulated MDPCL2 murine macrophages in vivo and in vitro acquired the ultrastructural features of apoptosis, such as condensed nuclear chromatic, nuclear fragmentation, cell shrinkage, and blebbing of the plasma membrane. Murine peritoneal macrophages and isolated rat Kupffer cells incubated in the medium containing liposome-encapsulated MDPCl2 increased DNA fragmentation in a dose-dependent manner. Electrophoretic analysis of extracted DNA from the isolated Kupffer cells showed DNA fragmentation. Another diphosphonate, Alendronate (4-amino-1-hydroxy-butylidene-1,1-diphosphonate) had less potent macrophage cytotoxicity. However, MDPCl2, Alendronate, and gadolinium chloride in solution were not cytotoxic to macrophages. These results implied that the intralysosomal accumulation of MDPCl2 generates signals to induce macrophage apoptosis.

Alendronate↗

PubMed1979

Effect of ethane-1-hydroxy-1,1-diphosphonate and vitamin D on bone mineralization.

Administration of large quantities of ethane-1-hydroxy-1,1-diphosphonate to growing chicks resulted in a decrease in percent bone ash and an increase in percent osteoid. The degree of inhibition of bone mineral accumulation was a function of both duration and quantity of ethane-1-hydroxy-1,1-diphosphonic acid administration. The inhibition of bone mineral accumulation could be partially corrected with administration of 1,25-dihydroxyvitamin D3. Administration of high levels of ethane-1-hydroxy-1,1-diphosphonate also resulted in inhibition of intestinal calcium absorption. This could be reversed or prevented by the administration of 1,25-dihydroxyvitamin D3.

Animals↗

PubMed1984

Effect of polyvinyl phosphonates and ethane hydroxy diphosphonate on mineralization of ectopic bone.

The effects of polymeric polyphosphonate and of ethane hydroxydiphosphonate on the development of ectopic bone were compared at different stages of bone development. The diphosphonate affected bone development at different stages, as reflected by alkaline phosphatase and aryl sulphatase activities, as well as by the creation of calcium ions by bone and on its readiness to undergo isotopic exchange. The polymeric polyphosphonate (mol. wt., 3500-8000), on the other hand, did not exhibit any of these effects, although it did inhibit the activity of the enzymes in vitro to an extent comparable with that of the diphosphonate. The results corroborate the assumption that the effects of polymeric polyphosphonates on hard tissues are confined to the extracellular space while the effects of diphosphonates on bone development are due to intracellular activity and not to sequestering of extracellular calcium.

Alkaline Phosphatase↗

PubMed1975

Quantitative determination of ethane-1-hydroxy-1,1-diphosphonate in urine and plasma.

A technique has been developed to measure the diphosphonate ethane-1-hydroxy-1, 1-diphosphonate (EHDP) quantitatively in 5 ml of urine or 2 ml of plasma. The procedure is based on a coprecipitation of EHDP with calcium phosphate, elimination of inorganic phosphate as an insoluble triethylamine-phosphomolybdate complex, decomposition of the P-C-P bond with ultraviolet light and spectrophotometric determination of the inorganic phosphate released. A trace amount of [14C] EHDP is used to correct for losses. The method appears specific for the diphosphonate, exhibits quantitative recoveries, and has a mean coefficient of variation of 3.7% for urine and 7.3% for plasma. The limit of detection is in the order of 2.5 mumol/1 in 5 ml urine and 0.5 mumol/1 in 2 ml of plasma.

Chemical Precipitation↗

PubMed1979

Treatment of calcium urolithiasis with diphosphonate: efficacy and hazards.

The effect of treatment of renal stone formation with 5 to 20 mg./kg. per day oral disodium ethane-1-hydroxy-1,1-diphosphonate for up to 30 months was examined in 12 patients with active renal (calcium) stone disease. The over-all incidence of stone passage decreased from 17.8 stones per year per patient before treatment to 7.7 stones per year per patient during therapy. Of the 12 patients 7 passed fewer stones or no stones during treatment. However, the incidence of stone passage was not changed substantially by disodium ethane-1-hydroxy-1,1-diphosphonate in 5 patients. Symptoms of muscle weakness and pain in the back, hips and shoulders occurred in 3 patients during treatment, 2 patients had an increase in serum alkaline phosphatase and 1 patient had a decrease in bone density. Although disodium ethane-1-hydroxy-1,1-diphosphonate may be clinically useful to manage calcium urolithasis in certain patients its over-all use is limited because of its ineffectiveness in some patients and owing to its potential to induce osteomalacia.

Administration, Oral↗

PubMed1982

On the action of prednisolone and ethane-1-hydroxy-1,1-diphosphonate (EHDP) on rabbit bone.

Ethane-1-hydroxy-1,1-diphosphonate (EHDP) (0.1 mg and 1 mg P/kg) and prednisolone (3.7 mg/kg) were administered separately and in combination to young rabbits for a period of 100 days. The results of the experiment show that EHDP is able to reduce the loss of bone substance per unit volume caused by prednisolone. The histological changes in the epiphyseal cartilage noted after prednisolone are not influenced by diphosphonate. The marked formation of fat marrow demonstrable in the prednisolone group does not occur in the prednisolone-diphosphonate group.

Animals↗

PubMed2002

Preparation, characterization, and structure of zirconium fluoride alkylamino-N,N-bis methylphosphonates: a new design for layered zirconium diphosphonates with a poorly hindered interlayer region.

This paper reports the preparation and characterization of the homologous series of layered zirconium fluoride n-alkylamino-N,N-bis methylphosphonates, of general formula ZrF(O(3)PCH(2))(2)NHC(n)H(2n+1) (n = 1, 2, 3, 4, 5, 6, 8, 9, 10), in which the two phosphonic groups of each diphosphonate building block participate in the assembly of a single lamella, because they are joined to zirconium atoms belonging to the same layer. The crystal structure of one of the series of these zirconium diphosphonates, ZrF(O(3)PCH(2))(2)NHC(5)H(11), has been solved "ab initio" by X-ray powder diffraction data. The structure is monoclinic, space group P2(1)/c. The zwitterionic character of the diphosphonate moiety is a distinctive feature which acts as a structure-orienting factor, generating a layer framework which is different from the other structures known for zirconium phosphates and phosphonates. This compound undergoes a phase transition at 117 degrees C which involves a rearrangement of the interlayer alkyl chains. The structure of the high-temperature phase has been refined by the Rietveld method. Because only one organic residue is associated with two phosphonate tetrahedra, a poorly hindered interlayer region is formed, and alkyl chains bonded to adjacent layers are interdigitated. Preliminary experiments have shown that these compounds are able to intercalate organic molecules, such as n-alkanols, from very dilute water solutions.

Journal Article↗

PubMed1975

The effects of a diphosphonate and dietary calcium on the metabolism of vitamin D3 (cholecalciferol) in the chick.

1. Vitamin D-deficient chicks, maintained on a diet adequate in calcium and treated with ethane-1-hydroxy-1,1-diphosphonate for 2 days before a single oral dose of cholecalciferol (vitamin D3), converted the vitamin into 24,25-dihydroxycholecalciferol instead of into the normal metabolite 1,25-dihydroxycholecalciferol. 2. This inhibition of the renal 1-hydroxylase disappeared on withdrawal of the diphosphonate. 3. Kidneys from chicks given diphosphonate for 12 days converted 25-hydroxycholecalciferol into 24,25-dihydroxycholecalciferol on incubation in vitro. 4. The inhibition of the 1-hydroxylase was markedly accelerated by treating the birds with cholecalciferol. 5. No inhibition of renal 1-hydroxylation was observed in birds maintained on a diet low in calcium. 6. A possible mechanism producing this effect is discussed.

Animals↗

PubMed1979

Regional 99m technetium diphosphonate uptake in experimental dog heart infarct: relation to duration and severity of ischaemia.

Regional uptake of 99mTechnetium diphosphonate was compared with regional myocardial blood flow 6, 12 and 24 h after the onset of myocardial infarction in dogs, and with regional creatine kinase depletion 24 h after the onset. Uptake of the imaging agent increased from 6 to 24 h, but no consistent relationship could be demonstrated between regional myocardial blood flow and regional uptake of the diphosphonate nor between uptake and regional creatine kinase depletion at the centre or border of the infarct. In addition, inappropriately high levels of 99m Technetium uptake could be demonstrated in the epicardial layer of the normal tissue surrounding the infarct. We conclude that diphosphonate uptake is not quantitatively related to the severity of ischaemia, and that use of this substance for imaging may over-estimate myocardial infarct size.

Animals↗

PubMed1988

Tc-99m diphosphonate uptake in malignant fibrous histiocytoma: a possible iron-related effect.

A man with malignant fibrous histiocytoma of the thigh had avid uptake of Tc-99m MDP in the lesion. Review of tissue sections showed considerable accumulation of iron in the tumor. Iron is known to be a potential nidus for deposition of the Tc-99m diphosphonates. A review was made of tissue sections from two other reported cases of malignant fibrous histiocytoma which also had significant accumulation of Tc-99m diphosphonates. Both revealed iron within the tumor. The origin of the iron is unknown (perhaps from necrosis and hemorrhage, from trauma, or from innate phagocytic activity of the histiocytes). However, this observation may serve as a stimulus to studies attempting to discern the underlying mechanisms of extraosseous deposition of the Tc-99m diphosphonates.

Adult↗

PubMed1997

Can (99m)technetium methylene diphosphonate bone scans objectively document costochondritis?

STUDY OBJECTIVES: To determine whether bone imaging with 99mTc methylene diphosphonate is a specific method of making the diagnosis of costochondritis in patients with chest pain who rule out for myocardial infarction. DESIGN: Nonblinded prospective controlled study in 20 patients and 10 control subjects. SETTING: Inpatient medical service of a tertiary teaching hospital. PATIENTS: Two hundred consenting patients admitted to the hospital with chest pain and suspected myocardial infarction were examined. Those in whom acute myocardial infarction was ruled out were evaluated for the clinical signs of costochondritis, ie, tenderness over one or more costochondral junctions. Twenty patients who met the clinical criterion gave informed consent and were subjected to bone imaging. Ten control subjects with cancer who did not have clinical signs of costochondritis underwent bone imaging to rule out metastatic disease (normal in all cases). INTERVENTIONS: Bone imaging with I.V. 99mTc methylene diphosphonate. MEASUREMENTS: Bone scans of the investigative patients and the control subjects were read by two independent nuclear medicine specialists. RESULTS: Sixteen of the 20 patients with clinically diagnosed costochondritis showed increased technetium uptake at all costochondral junctions bilaterally; six of them also had increased uptake elsewhere on the chest wall (sternum, manubrium, or first rib). All 10 of the control patients likewise showed increased technetium uptake at all costochondral junctions bilaterally. CONCLUSIONS: Bone imaging with 99mTc methylene diphosphonate is not a specific method of making the diagnosis of costochondritis.

Bone Neoplasms↗

PubMed1997

A comparison of whole-body turboSTIR MR imaging and planar 99mTc-methylene diphosphonate scintigraphy in the examination of patients with suspected skeletal metastases.

OBJECTIVE: This study was undertaken to compare whole-body turbo short inversion time inversion recovery MR imaging and 99mTc-methylene diphosphonate planar scintigraphy in the examination of patients with suspected skeletal metastases. SUBJECTS AND METHODS: Twenty-five patients with known or suspected skeletal metastatic disease underwent both whole-body turbo short inversion time inversion recovery MR imaging and whole-body 99mTc-methylene diphosphonate scintigraphy. RESULTS: MR imaging revealed metastases at 57 of 175 possible sites (sensitivity, 96.5%, specificity, 100%; positive predictive value, 100%). Scintigraphy revealed metastases at 43 of 175 possible sites (sensitivity, 72%; specificity, 98%; positive predictive value, 95%) (McNemar test, 0.01; p = .016). Discrepancies in skeletal evaluation by whole-body MR imaging and scintigraphy were observed in six (24%) of 25 patients. Soft-tissue abnormalities were identified in 13 (52%) of 25 patients with MR imaging alone. CONCLUSION: Preliminary results suggest that whole-body MR imaging is an effective method of examining patients with suspected skeletal metastases, with better sensitivity than conventional planar 99mTc-methylene diphosphonate scintigraphy.

Adult↗

PubMed1977

Detection of sacro-ilitis. A comparison between profile scanning with the use of 99m Tc pertechnetate and scintigraphy with 99m Tc diphosphonate.

Comparative evaluation of the sensitivity of 99mTc pertechnetate scanning and of 99mTc diphosphonate scintigraphy in detecting sacro-iliac arthritis (S.I.) was performed in 32 patients with definite S.I., 14 with probable S.I., and 6 with inactive S.I., 14 patients without any evidence of S.I. served as controls. Greater diagnostic accuracy was obtained by 99mTc pertechnetate scanning than with 99mTc diphosphonate scintigraphy in patients with active S.I. in the early stages before radiological changes had become evident and in patients 22 years old and younger. In patients with inactive S.I. a close correlation was found between clinical, radiological, and scintigraphical results with 99mTc diphosphonate scintigraphy. An index obtained by adding the uptake values measured by both methods in each subject yielded valuable information in patients with S.I. that is clinically difficult to differentiate.

Adolescent↗

PubMed1975

Improved brain scan specificity utilizing 99mTc-pertechnetate and 99mTc(Sn)-diphosphonate.

Each of 36 patients was studied with two separate brain scans performed sequentially after the injection of 20 mCi of 99mTc-pertechnetate or 20 mCi of 99mTc(Sn)-diphosphonate. The resulting scans were qualitatively compared, and lesion-to-nonlesion ratios of activity determined. Diagnoses were established by clinical criteria and were supported in the majority of cases by computerized axial tomography or roentgen angiography or both. Histologic confirmation was available in five cases of tumor and in the single cases of subdural hematoma and cerebral abscess. Of 22 cerebral infarctions, 15 were better demonstrated with 99mTc-(Sn)-diphosphonate than with 99mTc-pertechnetate. Of the seven remaining cases, three were visualized equally well with each agent, and three were better demonstrated with 99mTc-pertechnetate. One was not seen with either agent. Of the 12 tumors, 11 were visualized better with 99mTc-pertechnetate than with 99mTc-(Sn)-diphosphonate while in one case the lesion was seen equally as well with both agents. In no case was a lesion definitely seen with one radiopharmaceutical and not with the other. These results indicate that this dual method is helpful in differentiating gliomas and metastases from cerebral infarctions.

Adult↗

PubMed2005

[Methimazole versus methimazole and diphosphonates in hyperthyroid and osteoporotic patients].

AIM: It is well-know that hyperthyroidism is one of the key causes of secondary osteoporosis. High values of thyroid hormones increase the bone mineral turnover speed by promoting osteoclastic and osteoblastic activities. The aim of our study is to evaluate the increase of bone mineral density (BMD) in osteoporotic and hyperthyroid patients treated with only antithyroid drugs versus patients treated with antithyroid drugs and diphosphonates. METHODS: Twenty-six elderly male patients, 65-75 years, were selected. In all these patients, thyroid function (FT3, FT4, TSH, Tg, AbTg, AbTPO) was evaluated at baseline and after 6 and 12 months from the start of medical treatment; the following were evaluated: BMD, calcium serum, phosphorus serum, alkaline phosphatase, PTH and 24 hours urinary calcium, phosphorus and hydroxyprolin. Thirteen patients (group 1) were treated with antithyroid drugs (methimazole 5-20 mg/die/os) and diphosphonates (alendronate 10 mg/die/os). The control group of 13 patients (group 2) was treated with antithyroid drugs only. RESULTS: After 6 months of treatment, the patients of group 1 showed a mean increase of 2.5% in lumbar spine BMD compared with a mean increase of 0.3% in group 2 (p<0.01). After 12 months, group 1 showed a mean increase of 6.2% in lumbar spine BMD, compared with a mean increase of 2% in group (p<0.001). CONCLUSIONS: The combination of antithyroid and diphosphonates drugs appears to be more efficacious than antithyroid therapy alone for the treatment of osteoporosis in male hyperthyroid patients.

Aged↗

PubMedDate not supplied

[The influence of diphosphonic analogues of inorganic pyrophosphate on activity of RNA-polymerases from the calf thymus].

Diphosphonic analogues of inorganic pyrophosphate (PPi): methylene-, oxyethylidene-, aminomethylenediphosphonic acids as well as phosphonacetic, imidodiphosphoric bis- (phosphonomethyl)-phosphonic acids and methylenediphosphonic and phosphonic acid monoanhydrides were studied for their effect on the RNA-synthesizing activity of thymocytes. DNA-dependent RNA-polymerases I and II from the calf thymus nuclei were used for these studies. The analogues and PPi under study are shown to be inhibitors of both RNA-polymerases in nuclei from calf thymus and of purified RNA-polymerase II, which is more sensitive to the effect of diphosphonates. Methylenediphosphonic acid is the strongest inhibitor among the studied analogues, and imidodiphosphoric and phosphonacetic acids are the weakest inhibitors. Inhibition of purified RNA-polymerase II by diphosphonates has a complex character and includes both interaction of the PPi analogues with enzymes and chelating by them of Mn ions which are cofactors for RNA polymerase.

Animals↗

PubMed1986

Quantification of regional platelet and calcium deposition on pericardial tissue valve prostheses in calves and effect of hydroxyethylene diphosphonate.

Mitral valves were replaced with 25 mm bovine pericardial tissue valve prostheses (Ionescu-Shiley) in 45 calves (23 controls and 22 treated daily with hydroxyethylene diphosphonate). Before being killed 1, 14, 30, and 90 days later, the calves received In-labeled autologous platelets intravenously. Regional variations in platelet deposition were measured by a new technique. Thrombus was noted early on the flexion zone of the valve; with time it increased on the free edge and central zone. Platelet deposition was initially high on the flexion zone, attachment zone, sewing ring, and perivalvular tissue but decreased with time. Hydroxyethylene diphosphonate treatment tended to decrease platelet deposition in all zones. Calcium content was high in thrombus and increased in all zones with time, in both groups, but the deposition was less in the group treated with hydroxyethylene diphosphonate. Collagenous tissue and adherent thrombus appear to provide nucleation sites for calcification.

Animals↗