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M F Basle

Publications and source records attributed to M F Basle.

36 records · Page 2Linked to original sources
PubMed1994

[Electron microscopic study of a macroporous calcium phosphate ceramic implanted in an osseous site].

Cellular and tissular responses to intraosseous graft of a macroporous calcium phosphate ceramic was studied using transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Twelve specimens were implanted in 6 rabbits (tibiae), taken at day 14 after implantation and processed either for TEM (6 samples) or SEM (6 samples). As early as day 14 after implantation osteogenesis so that resorption of the newly formed bone and of the biomaterial, were observed at the surface of the ceramic, inside the macropores. Osteoblasts were clearly visible and well differentiated with abundant rough endoplasmic reticulum and large Golgi zone. The resorption processes were associated with 2 types of multinucleated cells. Based on ultrastructural observations (cellular characteristics and measurement of the microporosity) it appears that incompletely differentiated osteoclast was the major cell responsible of the biodegradation of the ceramic. These results suggest that the cellular events occurring at the surface of a macroporous calcium phosphate ceramic are similar to that observed in physiological bone remodelings.

Animals↗
PubMed1993

[Biomaterials for bone filling: comparisons between autograft, hydroxyapatite and one highly purified bovine xenograft].

Bone grafts are becoming increasingly common in orthopaedics, neurosurgery and periodontology. Twenty one New Zealand rabbits were used in the present study comparing several materials usable as bone substitutes. A 4.5 mm hole was drilled in the inner femoral condyles. Holes were filled with either an autograft (from the opposite condyle), an hydroxylapatite (Bioapatite), or a highly purified bovine xenograft (T650 Lubboc). Animals were sacrificed at 1, 3 and 6 months post implantation and a quantitative analysis of newly-formed bone volume (BNF/IV) and remaining biomaterials (BMAT/IV) was done. In addition, some holes were left unfilled and served as controls. At 6 months, there was no tendency for spontaneous repair in the control animals. The autografted animals have repaired their trabecular mass and architecture within the first month. Hydroxylapatite appeared unresorbed at six months and only thin and scanty new trabeculae were observed. The xenograft induced woven bone trabeculae formation on the first month. This was associated with resorption of the material by two multinucleated cell populations. At six months, the epiphyseal architecture was restored and the biomaterial has disappeared in most cases. Xenografts appear a promising alternative to autografts and allografts, whose infectious risks and ethical problems should always be borne in mind.

Animals↗
PubMed1991

[Bone density in idiopathic hypercalciuria in men. Study by dual photon absorptiometry, X-ray computed tomography and histomorphometry].

Lumbar bone mineral density (BMD) of the L3 vertebra was evaluated by double photon absorptiometry or tomodensitometry (TDM) in 55 hypercalciuric individuals in two separate studies. In the first, in a department of nephrology, 29 lithiasis patients were studied by TDM of L3. By this technique, trabecular density was 75 +/- 23% of normal. It was lower in the 17 patients in whom hypercalciuria persisted after calcium restriction (66 +/- 15% of normal and below the "fracture threshold" in 9 cases) than in the 12 patients in whom it disappeared after the prescription of such a diet (88 +/- 26%, below the "fracture threshold" in 3 cases), this difference being significant (p less than 0.01). In another 26 patients, seen in a department of rheumatology, three of whom had osteoporosis with vertebral fracture, density was measured in 21 cases by double photon absorptiometry (mean Z score -1.9 +/- 1.0) and in 5 cases by TDM (mean BMD of L3 69 +/- 21% of normal). Mean iliac trabecular volume, measured in 8 cases only, was 70 +/- 25% of normal and was below the "fracture threshold" in 3 cases. Comparison of the two study groups was not possible because of differences in recruitment and methods of investigation. These two studies nevertheless show the existence of significant vertebral bone rarefaction during hypercalciuria in the young man. Confirmed and quantified in patients in whom the metabolic disturbance was discovered as a result of radiological abnormalities, this quantitative abnormality was also seen in patients in whom hypercalciurie was found because of renal lithiasis.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon↗
PubMed1991

Aminohydroxypropylidene bisphosphonate (AHPrBP) treatment of severe immobilization hypercalcaemia in a young patient.

We report a case of severe hypercalcaemia in a 16-year-old patient, 24 weeks after immobilization for quadriplegia. The biochemical and histomorphometric parameters showed increased osteoclastic resorption and decreased osteoblastic formation. Hydration, chair sitting, salmon and porcine calcitonin, sodium etidronate were unable to normalize the hypercalcaemia. The new antiosteoclastic agent, 3-amino-1 hydroxypropylidene-1, 1-bisphosphonate (AHPrBP), was effective in normalizing serum calcium and biochemical parameters of osteoclastic activity within five days. Bone histomorphometry showed a marked reduction in osteoclastic activity after AHPrBP treatment, as well as a drastic depression of osteoblastic activity, presumably due to the reduction of bone turnover. This case represents to our knowledge, the first successful use of AHPrBP in the treatment of immobilization hypercalcaemia.

Adolescent↗
PubMed1988

Isolation of osteoclasts from Pagetic bone tissue: morphometry and cytochemistry on isolated cells.

Giant osteoclasts and other cells were isolated from Pagetic bone tissue using 0.5 mM ethylene diamine tetraacetic acid on bone samples from 8 patients with Paget's disease. The cell suspension contained osteoclasts and osteoblasts as well as some mononuclear cells such as monocytes. The number of nuclei in isolated osteoclasts (33.85 +/- 20.92 nuclei/osteoclast) correlates fairly well (p less than 0.02) with the number of nuclei counted on histologic sections (15.88 +/- 11.80 nuclei/osteoclast) for samples from each patient. Enzyme histochemistry demonstrated acid phosphatase activity in isolated osteoclasts and in mononucleated cells, such as monocytes. Alkaline phosphatase was detected only in osteoblasts while succinate dehydrogenase was observed in osteoclasts, osteoblasts and monocytes. Esterases, such as nonspecific aliesterase and specific naphthol AS-D acetate esterase, were identified in osteoclasts and in macrophages. Inhibition of specific naphthol AS-D acetate esterase in osteoclasts by addition of sodium fluoride suggests that the enzyme could be of monocytic origin.

Esterases↗
PubMed1987

Sarcomatous degeneration in Paget's bone disease.

The authors report 12 cases (8 men and 4 women) of sarcomatous degeneration in Paget's bone disease, with an average age of 72.3 years. Sarcomatous degeneration occurred often in polyostotic Paget's disease, and osteitis deformans was seen in 4 cases. Femur and pelvis were the most affected bones. Pain was a constant feature, whereas tumefaction and fracture were less common. Osteolytic lesions were more frequent than condensed or mixed lesions and radiological signs of malignancy were usually found. Seven cases were histologically classified as osteogenic sarcoma and 3 cases as fibrosarcoma. Electron microscopy was performed on 2 osteogenic sarcomas and in 1 case revealed microcylindrical inclusions in Pagetic osteoclasts and in multinucleated giant tumor cells, but none in mononucleated tumor cells. The average survival time for the patients in this study was only 4.5 months.

Aged↗
PubMed1987

Transient hypoparathyroidism induced by synthetic human parathyroid hormone-(1-34) treatment.

Daily injections of low doses of a synthetic fragment of human PTH [hPTH-(1-34) have increased iliac trabecular bone volume when used in the treatment of osteoporosis. In approximately 50 patients no major side-effects had occurred. However, during daily sc 100-micrograms injections of the peptide, one patient repeatedly developed parathyroid hypofunction which resolved each time treatment was stopped. Specific immunoglobulin G (IgG) antibodies binding [125I]hPTH-(1-34) were identified in the patient's serum, and positive immunohistochemical reactions were obtained when bovine parathyroid sections were exposed to the patient's IgG. After adsorption with PTH, the patient's IgG, free of anti-PTH antibodies, reacted with renal cell membranes, as demonstrated by indirect immunofluorescence and blocked renal PTH-dependent adenylate-cyclase activation in vitro. These results support the hypothesis that anti-PTH receptor as well as anti-PTH antibodies were generated during hPTH-(1-34) treatment, which led to the development of hypoparathyroidism when their titers were high.

Adenylyl Cyclases↗
PubMed1987

[Serum concentrations of 1,25-dihydroxyvitamin D in cases of osteomalacia, parathyroid dysfunction and idiopathic hypercalciuria].

1,25 dihydroxyvitamin D (1,25(OH)2 D) is the active metabolite of vitamin D and has an essential role in bony metabolism on the regulation of the calcium-phosphorus balance. The circulating level of 1,2(OH)2 D is normally between 25 and 45 pg/ml. Isolation of the fraction to be titrated requires sophisticated purification techniques using high performance chromatography (HPLC). In osteomalacia secondary to a deficiency the mean level of 1,25(OH)2 D is low (14.1 +/- 6.9 pg/ml) because of substratum deficiency. Administration of vitamin D supplements is quickly followed by a supraphysiological increase of the level of active metabolite. The role of the parathyroid hormone on the activity of 1-hydroxylase is illustrated by the results of the titration in parathyroid dysfunctions: decrease of the mean level in hypoparathyroidism (18 +/- 6.9 pg/ml), and on the contrary, a significant increase in hyperparathyroidism (56.6 +/- 15.4 pg/ml) despite of a spread of the individual values. In 18 cases of idiopathic hypercalciuria, we have only observed an increase of 1,25(OH)2 D level, in two cases. Titration of 1,25(OH)2 D complements the calcium-phosphorus evaluation to precise the physiopathogenic mechanism of the disorders observed in various diseases. Its interpretation requires the joint measurement of the substratum level, 25-hydroxyvitamin D, and the evaluation of the parathyroid function.

Adult↗
PubMed1986

[Contribution of modern research technics to the identification of a virus in Paget's disease of bone].

The morphological resemblance between osteoclast inclusions in Paget's bone disease and viral structures has encouraged new research with immunocytologic methods and In Situ hybridization. Paramyxovirus antigens of measles virus and respiratory syncitial virus were detected in pagetic osteoclasts using polyclonal antibodies. Paramyxovirus antigens of measles virus, simian virus (SV 5) and human parainfluenza virus (PF 3) were demonstrated using monoclonal and monospecific polyclonal antibodies. Measles virus nucleotide sequences were detected in pagetic osteoclasts by In Situ hybridization with a 3H labelled cDNA probe specific for measles nucleocapsid protein. However, the same probe also hybridized with several types of mononucleated cells suggesting a wide host range for measles virus genomic information. Apparently, this viral information is translated only in the osteoclasts. The link between the presence of viral information in pagetic bone tissue cells and Paget's disease itself still awaits elucidation.

Bone and Bones↗
PubMed1985

Paramyxovirus antigens in osteoclasts from Paget's bone tissue detected by monoclonal antibodies.

The fluorescent antibody technique using both monoclonal and specific polyclonal virus antibodies was applied to investigate the nature of the inclusions seen in the abnormal osteoclasts associated with Paget's bone disease. The results show that antigens of measles virus, simian virus 5 (SV5) and human parainfluenza virus type 3 (PF3) could be detected in the osteoclasts but not in control bone cells. Measles and SV5 nucleoprotein (NP) and haemagglutinin-neuraminidase (HN) antigens were apparently present in all the cases of Paget's disease examined, whereas PF3 NP and HN antigens were present only in some of the cases. These investigations suggest that paramyxoviruses may play a role in the aetiology of the bone disease.

Antibodies, Monoclonal↗
PubMed1985

[Cellular aspects of reorganization of pagetic bone tissue].

The light microscopy features of the cellular reorganisation of tone tissue in Paget's disease are well known. They result in the constitution of abnormal bone tissue. Ultrastructural studies have enabled a more detailed study of osteoblasts, osteocytes and osteoclasts. Osteoclasts are the only cells which present abnormalities. In particular, we observe intranuclear and intracytoplasmic inclusions composed of microcylinders. The morphological analysis is able to relate the presence of these formations with a viral infection of the paramyxovirus group. The results obtained by immunocytochemical techniques support this hypothesis. The osteoclast lesion could be a determining factor in the abnormal reorganization of bone tissue in Paget's disease, which may be considered to be a disease due to a slow acting virus.

Bone and Bones↗
PubMed1984

Bone tissue in Paget's disease treated by ethane-1, hydroxy-1, 1 diphosphonate (EHDP). Structure, ultrastructure, and immunocytology.

Diphosphonates have been used in the management of Paget's disease of bone because of their experimentally demonstrated antiosteoclastic activity. Light microscopic examination of bone tissue from 13 patients with Paget's bone disease who were receiving (EHDP) treatment showed considerably reduced osteoclastic resorption accompanied by gradual replacement of irregular woven bone by lamellar tissue. Electron microscopic examination confirmed that pagetoid osteoclasts are morphologically abnormal cells and degenerate after EHDP treatment. EHDP does not affect the measles nucleocapsid-like inclusions in the osteoclast nuclei. Immunocytologic analysis showed that during EHDP treatment viral antigens of the measles type persist in the cytoplasm and nuclei of osteoclasts even when these cells are greatly altered. These findings support the hypothesis of a viral etiology in Paget's disease of bone.

Aged↗
PubMed1983

Bone tissue in reflex sympathetic dystrophy syndrome--Sudeck's atrophy: structural and ultrastructural studies.

Light and electron microscopic examination of bone in reflex sympathetic dystrophy syndrome confirms that vascular disorders play an important role in the genesis of bone lesions. These vascular disorders lead to degeneration of osteocytes and demineralization of bone, with the disappearance of hydroxyapatite crystals. The neo-osteogenesis that follows resembles the different stages of fracture repair, with precocious elaboration of irregular, replacement woven bone, followed by osteoclastic resorption and the laying down of lamellar bone trabeculae. The bone lesions clearly appear to be a consequence of autonomic nervous system circulatory disorders.

Adolescent↗
PubMedDate not supplied

[Cortisone-induced osteoporosis: from physiopathology to treatment].

Corticosteroid-induced osteoporosis, the principal cause of "secondary" osteoporosis, is usually observed in patients under prolonged systemic corticosteroid therapy and results from the multiple effects exerted by these drugs on bone cell metabolism. Corticosteroids reduce the intestinal absorption of calcium and its tubular reabsorption, thereby negativating the calcium balance and inducing a parathyroid reaction. This reaction is responsible for an increase in bone cell remodelling, but the main manifestation of the direct effect of corticosteroids on bone is osteoblast depression, so that there is disparity between bone resorption and formation, which in turn is responsible for bone tissue deficit. Sex hormone deficiency (due to menopause or treatment) and lack of physical activities (due to the causal disease or to iatrogenic myopathy) amplify bone rarefaction. By quantifying the bone loss, modern densitometry methods provide an early risk evaluation. Osteoporosis of varying intensity exposes some 20% of patients to fractures, vertebral collapse and rib fractures. Preventive measures are always recommended, including minimal effective dose corticosteroid therapy, sodium-free diet, calcium and vitamin D supplement, sex hormone replacement and pursuance of physical activities. Once the stage of fractures by osteoporosis has been reached, the "curative" treatment aims at reducing the incidence of new fractures, either by slowing down osteoclast resorption, or by restoring the bone tissue reserve through stimulation of the osteoblasts. The usefulness of these therapeutic measures in the preventive treatment of corticosteroid-induced osteoporosis remains controverted.

Adrenal Cortex Hormones↗
PubMedDate not supplied

The early remodeling phases around titanium implants: a histomorphometric assessment of bone quality in a 3- and 6-month study in sheep.

The purpose of this study was to evaluate the quality of the bone matrix around commercially pure titanium implants at 3 and 6 months postplacement in sheep. Implants were placed in the corticotrabecular areas of both femurs in 6 animals. Each animal received 4 Euroteknika implants in the right femur and 4 Nobel Biocare implants in the left femur. Bone blocks containing the implants were studied undecalcified after being embedded in methylmethacrylate. Sections were stained with toluidine blue and basic fuchsin. The amount of bone around the implants, the contact interface between the implant and bone, and the mineral apposition rates were measured. The fractional amount of woven bone could be quantified because of its high glycosaminoglycan content. No differences could be observed between the 2 types of implants. Total bone volume did not increase around both types of implants between 3 and 6 months, indicating that ankylosis was rapidly achieved. In contrast, in the area in contact with the implant, the bone-titanium interface drastically increased and the mineral apposition rate decreased. The fractional volume of woven bone around implants was considerably reduced after 6 months. Bone quality around implants was improved at 6 months (volume of woven bone near zero), and true osteonic structures were observed in close contact with titanium. The remodeling process appeared to improve bone quality and increase the bone-titanium interface around implants, while the net bone quantity necessary to immobilize implants was achieved rapidly and remained unchanged.

Animals↗