Barbara G. Mills

Florid osseous dysplasia. A clinical-pathologic study of thirty-four cases.

Thirty-four patients with florid osseous dysplasia were studied. The majority were asymptomatic Negro women: Seventeen biopsy-proven simple bone cysts were found in affected quadrants of fourteen patients. Radiographs displayed a spectrum of sclerotic and ground-glass opacities limited to alveolar processes but not to root apices. Biopsy material was studied in all cases, and biochemical analyses of serum and cyst fluid were performed on some patients. Test results and skeletal radiographs indicate that the disease is limited to the jaws. Patients have remained asymptomatic with little alteration of radiographic patterns. Three cysts failed to heal following treatment, others filled with radiographically abnormal tissue. Chronic osteomyelitis may infrequently complicate the disease. These cases appear to represent the most exuberant manifestation of this reactive fibro-osseous jaw disease.

Magnesium deficiency: effect on bone and mineral metabolism in the mouse.

Insufficient dietary magnesium (Mg) intake has been associated in humans with low bone mass. Mg deficiency in the rat has suggested bone loss is due to increased bone resorption and/or inadequate bone formation during remodeling. The purpose of this study was to assess the effect of a low Mg diet on bone and mineral metabolism in the young and mature BALB/c mouse and explore the hypothesis that inflammatory cytokines may contribute to Mg deficiency-induced osteoporosis. Using an artificial diet, we induced targeted Mg depletion (0.002% Mg) with all other nutrients maintained at the normal level. In all Mg-depleted mice, hypomagnesemia developed and skeletal Mg content fell significantly. The serum Ca in Mg-deficient mice was higher than in control mice; however, serum PTH levels were not significantly different. Osteoprotegerin (OPG) in dosages that inhibit osteoclastic bone resorption did not prevent hypercalcemia in Mg-deficient animals. No significant difference in serum Ca was observed between groups when dietary Ca was reduced by 50%, suggesting that a compensatory increase in intestinal absorption might account for the hypercalcemia. Growth plate width decreased 33% in young Mg-deficient animals and chondrocyte columns decreased in number and length, suggesting that Mg deficiency reduced bone growth. Trabecular bone volume in the metaphysis of the tibia in these animals was decreased and osteoclast number was increased by 135%. Osteoblast number was significantly reduced. Immunohistochemistry revealed that substance P increased 230% and 200% in megakaryocytes and lymphocytes, respectively, after 1 day of Mg depletion. IL-1 increased by 140% in osteoclasts by day 3 and TNFa increased in osteoclasts by 120% and 500% in megakaryocytes on day 12. This study demonstrates a profound effect of Mg depletion on bone characterized by impaired bone growth, decreased osteoblast number, increased osteoclast number in young animals, and loss of trabecular bone with stimulation of cytokine activity in bone.

Evidence for Both Respiratory Syncytial Virus and Measles Virus Antigens in the Osteoclasts of Patients with Paget??s Disease of Bone

Recent ultrastructural and immunohistochemical evidence supports the hypothesis that Pagets disease of bone is a slow viral infection of the Paramyxoviridae family. Conflicting evidence for the presence of respiratory syncytial virus (RSV), a pneumovirus, or measles, a morbillivirus, has been reported. By the indirect fluorescent antibody assay, four RSV antisera were compared with four measles antisera on serial sections of pagetic bone or replicate coverslips of cells from pagetic bone grown in culture from 30 patients. Results produced positive immunofluorescence for RSV in 28 of 29 patients and positive immunofluorescence for measles in 11 of 22 patients. Of the 20 patients from whom comparable samples could be tested for antigens, 11 were found to harbor both antigens. These studies support the hypothesis that Pagets disease of bone is a slow viral infection of the Paramyxoviridae family more closely related to the pneumoviruses than the morbilliviruses.

Expansile Skeletal Hyperphosphatasia: A New Familial Metabolic Bone Disease†‡

We describe a new familial metabolic bone disease characterized by expanding hyperostotic long bones, early onset deafness, premature tooth loss, and episodic hypercalcemia. The condition affects a mother and daughter studied at the age of 36 years and 11 years, respectively. Both individuals lost all hearing in early childhood and suffered premature shedding of teeth. Skeletal pains began just before puberty. Swelling and aching of most middle phalanges in the hands is an especially troublesome manifestation. The mother also had episodes of symptomatic hypercalcemia first documented in late childhood and subsequently during intercurrent illness and postpartum lactation. Radiographs show hyperostosis and/or osteosclerosis predominantly in the skull and appendicular skeleton. Long bones also are expanded considerably, especially the middle phalanges in the fingers. The mothers skeletal abnormalities are more severe. Biochemical parameters of bone turnover, including serum alkaline phosphatase (ALP) activity, are elevated substantially. In the proposita, dynamic histomorphometry of nondecalcified sections of iliac crest revealed rapid skeletal remodeling. In the mother, who had been treated with bisphosphonates, electron microscopy (EM) showed disorganized collagen bundles as well as necrotic and apoptotic bone cells but no osteocytic osteolysis. Measles virus gene transcripts were not detected in peripheral blood monocytes. Karyotyping was normal, 46,XX. Hyperphosphatasia with bone disease previously has been reported as either a sporadic or autosomal recessive condition. Expansile skeletal hyperphosphatasia (ESH) is probably inherited as an autosomal dominant trait with a high degree of penetrance.

Immunohistochemical evidence of measles virus antigens in active otosclerosis.

Despite intensive investigation, the cause of otosclerosis remains uncertain. Recent studies of Pagets disease of bone have revealed a possible viral origin. Because of similarities between otosclerosis and Pagets disease, we have pursued investigation of a possible viral cause of otosclerosis. Four temporal bone specimens from patients with otosclerosis, processed for immunohistochemistry, demonstrated positive specific reactivity with monoclonal antibodies to measles virus antigens using the indirect immunofluorescent and immunoperoxidase techniques. Reactivity was most intense in active foci. Reactivity in the peroxidase assay was also observed in areas of active otosclerosis with application of primary antisera from patients with subacute sclerosing panencephalitis, a disorder of the central nervous system in which a defective measles virus has been isolated. Other related paramyxoviruses, including mumps and respiratory syncytial virus, were negative, as were negative controls.

Multinucleated cells formed in vitro from Paget's bone marrow express viral antigens

Pagets disease of bone is characterized by large numbers of osteoclasts that have viral-like nuclear and/or cytoplasmic inclusions. Pagetic osteoclasts express respiratory syncytial viral (RSV) and measles viral (MV) nucleocapsid antigens. The data suggest a possible viral etiology for Pagets disease. However, studies to characterize further the putative viral inclusions in Pagets osteoclasts have been severely hampered by the extreme difficulty in isolating large numbers of osteoclasts from pagetic bone. The recent demonstration that osteoclast-like multinucleated cells (MNC), that had certain characteristics of pagetic osteoclasts formed in marrow cultures from Pagets patients, may permit studies to describe this virus further. Therefore, we have cultured marrow samples from involved and uninvolved bones from Pagets patients and from normal subjects to determine if the MNC formed in these cultures express viral antigens. RSV and/or MV antigens were expressed in the mononuclear cells and/or the MNC formed in 12 of 12 marrow cultures from active lesions of patients with Pagets disease, with 40-50% of the cells expressing viral antigens. In contrast, less than 5% of cells isolated from cultures from normal subjects expressed RSV and/or MV. These results suggest that MNC formed in long-term marrow cultures from patients with Pagets disease frequently express paramyxoviral antigens and are very similar to pagetic osteoclasts. Thus, these marrow cultures may be useful for further characterizing the virus in Pagets disease.

ACUTE EFFECTS OF CALCITONIN ON OSTEOCLASTS IN MAN

To determine the mechanism by which calcitonin acutely decreses bone resorption in man, salmon or human calcitonin was administered intravenously to five patients with Pagets disease of bone immediately after an iliac crest bone biopsy. After 30 min an adjacent bone biopsy was taken and both were evaluated by light and electron microscopy. The results indicated that calcitonin both decreases the number of osteoclasts and alters the ultrastructure of these cells. These acute effects of calcitonin on osteociasts confirm findings in other species and provide evidence in man that calcitonin, at least in part, retards bone resorption by inhibiting osteoclastic activity.

Long-term culture of cells from bone affected by Paget’s disease

SummaryCells obtained from surgical bone specimens of eight patients with Paget’s disease of bone were maintained in culture for up to 8 months and seven passages. The doubling time during the period of maximal cell growth ranged from 4 to 12 days. Evidence consistent with the hypothesis that many of the cells were bone cells included the following: (a) histochemical techniques demonstrated staining of some cells for alkaline phosphatase or acid phosphatase and succinic dehydrogenase; (b) parathyroid extract stimulated increased uptake of3H-thymidine and3H-uridine; (c) parathyroid extract suppressed and salmon calcitonin stimulated uptake of3H-proline; and (d) crystalline calcium deposits were found within cells and extracellularly.Ultrastructural analysis revealed that three of the eight cultures contained cells whose nuclei had inclusions which were almost identical to those found in the osteoclast nuclei of all patients with Paget’s disease. The maintenance of cells derived from pagetic bone in long-term culture should aid in testing the hypothesis that Paget’s disease represents a slow virus infection of bone.

Ultrastructural and Immunohistochemical Evidence of Measles Virus in Active Otosclerosis

Because of the similarity between otosclerosis and Pagets disease of bone, and the mounting evidence of a viral cause in Pagets disease, we have investigated a possible viral cause for otosclerosis. Transmission electron microscopy of stapes footplate fragments with active otosclerosis has revealed structures morphologically identical with measles virus nucleocapsid in osteoblasts and preosteoblasts. Immunofluorescence and immunoperoxidase studies have confirmed the presence of measles nucleocapsid antigen in active lesions. Application of sera from patients with subacute sclerosing panencephalitis, a defective measles virus infection of the central nervous system, resulted in positive immunoreaction in areas of active otosclerosis.

Intramyocardial diversion of coronary blood flow: Effects of isoproterenol-induced subendocardial ischemia

Abstract Isoproterenol was found to have produced adverse reactions in eight of our patients. All demonstrated large negative ST segment shifts. In experimental studies in rats, the J-shift of the electrocardiogram was sensitive to low doses of isoproterenol. Combined use of a nitrate and beta-blocker completely reversed the significant negative J-shift depression induced by isoproterenol. Dog studies using platinum electrodes to measure intramyocardial oxygen tension at the epicardium and endocardium documented an intracardiac diversion of blood flow between the subendocardium and subepicardium. Isoproterenol diverted blood flow away from the subendocardium, which is very vulnerable to ischemia and decreased perfusion. This isoproterenol-induced “coronary steal” is probably due to localized hypoxia at the subendocardium. Nitroglycerin and propranolol both selectively increased subendocardial blood flow with little effect at the subepicardium. The regulation of blood flow through the coronary circulation can be explained in part by an intramyocardial diversion phenomenon.