Search PubMed⌕ Search

Biomedical subjects

J M Lane

Publications and source records attributed to J M Lane.

At least 145 records · Page 8Linked to original sources
PubMed1986

Chondrosarcoma.

Chondrosarcoma is a malignant cartilage-forming tumor that affects predominently the middle-aged population. There are three histologic grades, but differentiation of Grade I tumors from enchondromas can be difficult. The measurement of polypoidy (augmented chromosomal content per cell) appears to offer a method of segregation of benign from low-grade from high-grade tumors. With the exception of the high-grade spindle elements, current chemotherapy does not appear to affect chondrosarcomas. Retinoic acid, however, by enhancing lysosomal enzyme release, may be a potential efficacious therapeutic agent. Enhanced tumor staging as provided by the computed tomographic (CT) scan has demonstrated the boundaries for wide surgical excisions, most notably internal hemipelvectomies for low- and moderate-grade pelvic chondrosarcomas. Currently, low-grade chondrosarcomas have an overall five-year survival of 65%--85% in contradistinction to 15% for the highest grade chondrosarcomas.

Adult↗
PubMed1985

Treatment of neoplastic epidural cord compression by vertebral body resection and stabilization.

The results of treatment of neoplastic spinal cord compression by vertebral body resection and immediate stabilization in 101 consecutive patients over a 5-year period have been analyzed. Sites of primary cancer included the lung (25 patients), kidney (15 patients), breast (14 patients), connective tissue (12 patients), and a variety of others (35 patients). Of the 101 patients, 23 received surgery de novo; the remaining 78 patients had undergone previous therapy. Sites of involvement included the cervical region in 13 patients, the thoracic region in 68 patients, and the lumbar region in 20 patients. Prior to surgery, severe pain was noted in 90% of the patients, and 45% were non-ambulatory. Using an anterolateral surgical exposure, the vertebral body was resected along with all epidural tumor. Immediate stabilization was achieved with methyl methacrylate and Steinmann pins. Following surgery, the overall ambulation rate was 78%, and 85% of patients experienced pain relief. Of the 23 patients who had received no prior therapy, 90% continued to be ambulatory at their last follow-up examination or until death. The authors believe that surgery prior to irradiation is indicated in selected patients with neoplastic cord compression. In patients with solitary osseous metastasis to the spine, potentially curative resection can be undertaken if surgery is performed when the tumor is still confined to the vertebral body.

Adolescent↗
PubMed1985

Solid leukemic tumor. An uncommon presentation of a common disease.

Granulocytic sarcoma of the clavicle occurred in a 17-year-old boy. The patient had a densely sclerotic bony lesion with periosteal reaction and no peripheral blood manifestations of leukemia. Supraclavicular adenopathy developed after a preliminary diagnosis of Ewing's sarcoma was made, and a second biopsy was performed. Electron microscopy of the tissue showed Auer bodies and Charcot-Leyden granules characteristic of acute myelogenous leukemia. Combination chemotherapy, local irradiation, and clavicular resection have left the patient with no evidence of disease 50 months after diagnosis. Leukemia may appear as a solitary bone tumor before hematologic changes develop. Granulocytic sarcomas can have the radiographic and histologic appearance of primary bone tumors. Bone marrow examination and electron microscopy of biopsy tissue are diagnostic of leukemia and are important in all hospital investigations of round-cell tumors of bone.

Adolescent↗
PubMed1985

Energy cost during gait in osteosarcoma patients after resection and knee replacement and after above-the-knee amputation.

We determined the energy cost during gait by measuring the oxygen consumption of twenty-six patients after treatment for osteosarcoma about the knee. Fourteen had had an en bloc resection of the distal end of the femur and proximal end of the tibia followed by segmental replacement with a custom-made knee prosthesis and twelve had had an above-the-knee amputation followed by fitting with an artificial limb. Comparisons of free-walking velocity, oxygen consumption per meter traveled, and per cent of maximum aerobic capacity used during walking demonstrated that patients with resection and prosthetic knee replacement had a lower energy cost during gait.

Adolescent↗
PubMed1985

Structural scoliosis in osteoporotic women.

Fifty women (mean age 69 +/- 5 years) with biopsy-proven osteoporosis and back pain were radiographically studied for scoliosis, kyphosis, and compression fractures. Twenty-four (48%) osteoporotics had at least 10 degrees of structural scoliosis. Curves were indistinguishable from those of idiopathic scoliosis. Lumbar and thoracolumbar curves were most common. The kyphosis averaged 70 degrees +/- 17 degrees and spanned 9.8 +/- 1.75 vertebrae. Forty-seven patients had 140 compression fractures. Fractures occurred within, but were usually not the cause of, scoliotic curves. Scoliosis in elderly women is a clinical marker and may be a risk factor for osteoporosis and compression fractures. Adult scoliotic patients should be evaluated for osteoporosis with iliac bone biopsies and aggressively treated.

Aged↗
PubMed1985

The coexistence and characteristics of osteoarthritis and osteoporosis.

We defined the clinical features and radiographic coexistence of osteoarthritis and osteoporosis in fifty women with primary coxarthrosis and fifty age-matched women (average age, 69 +/- 5 years) with idiopathic osteoporosis. The patients with osteoarthritis had undergone total hip replacement. The diagnosis of primary osteoarthritis was established by clinical, radiographic, and histological criteria, and the diagnosis of osteoporosis was confirmed by histomorphometric analysis of specimens taken at iliac-bone biopsy. In the arthritic patients, spinal osteoporosis was identified by radiographic evidence of compression fractures, kyphosis, and scoliosis. Femoral osteoporosis was demonstrated by the index of Singh et al. and the femoral canal-shaft ratio. In the osteoporotic patients coxarthrosis was measured radiographically by the scale of Kellgren and Lawrence. On the average, the osteoporotic patients were twelve kilograms lighter than the osteoarthritic patients. Fifty-eight per cent of the osteoporotic and 18 per cent of the osteoarthritic patients had a scoliotic curve of at least 10 degrees. The prevalence of osteoarthritis of the hip in the osteoporotic women was 4 per cent, and the prevalence of compression fractures in the arthritic women was 6 per cent, which was approximately one-quarter of the expected incidence. These results show that: (1) osteoporosis does not protect against the development of coxarthrosis, (2) coxarthrosis is a negative risk factor for osteoporotic compression fractures, and (3) scoliosis and an ectomorphic habitus are clinical markers that identify a risk for osteoporosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1984

Mortality among diabetic patients using continuous subcutaneous insulin-infusion pumps.

Because of concern about deaths among diabetic patients using continuous subcutaneous insulin-infusion pumps, we conducted an investigation to determine whether the number of such deaths was excessive. By October 1982 we had identified 35 deaths among the estimated 3500 diabetic patients using pumps in the United States. The observed number of deaths was not greater than the expected number calculated from age-specific death rates for conventionally treated patients with Type I diabetes. The causes of death were not unusual, with two exceptions. One death was associated with malfunction of the device, and the other was attributed to acute bacterial endocarditis that arose from an abscess at the catheter-insertion site. Patients who died had high rates of autonomic neuropathy (66 per cent) and renal disease (39 per cent with serum creatinine levels above 5 mg per deciliter). We conclude that the use of continuous subcutaneous insulin-infusion pumps is not associated with excess mortality. However, certain types of patients may be at greater risk for death, and physicians should take great care in selecting patients for pump therapy.

Adolescent↗
PubMed1984

Relationship of oxygen and glutathione in protection against carbon tetrachloride-induced hepatic microsomal lipid peroxidation and covalent binding in the rat. Rationale for the use of hyperbaric oxygen to treat carbon tetrachloride ingestion.

CCl4 exerts its toxicity through its metabolites, including the free radicals CCl3. and CCl(3)00.. Oxygen strongly inhibits the hepatic cytochrome P-450-mediated formation of CCl3. from CCl4 and promotes the conversion of CCl3. to CCl(3)00.. Both these free radicals injure the hepatocyte by causing lipid peroxidation and binding covalently to cell structures. A reduced glutathione (GSH)-dependent mechanism can protect the liver microsomal membrane against CCl4-induced damage under aerobic conditions but not under anaerobic conditions (Burk, R.F., K. Patel, and J.M. Lane, 1983, Biochem. J., 215:441-445). Experiments were carried out using rat liver microsomes to examine the effect of O2 tensions found in the liver and of GSH on CCl4-induced covalent binding and lipid peroxidation. An NADPH-supplemented microsomal system was used. CCl4 or 14CCl4 was added to the sealed flask that contained the system, and after 20 min CHCl3 production, thiobarbituric acid-reactive substances (an index of lipid peroxidation), and covalent binding of 14C were measured. O2 tensions of 0, 1, 3, 5, and 21% were studied. Increases in O2 tension caused a fall in CHCl3 production, which indicated that it decreased CCl3.. GSH had no significant effect on CHCl3 production at any O2 tension. Lipid peroxidation and covalent binding of 14C fell progressively as O2 tension was increased from 1 to 21%. The addition of GSH decreased both lipid peroxidation and covalent binding, but did so better at the higher O2 tensions than at the lower ones. These results indicate that low O2 tensions such as are found in the centrilobular areas of the liver favor conversion of CCl4 to free radical products which cannot be detoxified by the GSH-dependent mechanism. They suggest that hyperbaric O2 might decrease free radical formation in the liver in vivo and promote formation of CCl(3)00. from CCl3.. This should result in diminished CCl4-induced lipid peroxidation and liver damage. Rats given CCl4 (2.5 ml/kg) were studied in metabolic chambers. Production of CHCl3 and ethane, the latter an index of lipid peroxidation, were measured. Rats in two atmospheres of 100% O2 produced much less CHCl3 and ethane than rats in air. This strongly suggests that hyperbaric O2 is decreasing free radical formation from CCl4 and/or promoting the formation of CCl(3)00. from CCl3.. These results provide the rationale for the use of hyperbaric O2 in the treatment of CCl4 ingestion.

Animals↗
PubMed1984

Primary osteogenic sarcoma of the femur: a model for the use of preoperative chemotherapy in high risk malignant tumors.

The value of adjuvant chemotherapy in primary osteogenic sarcoma (OSA) is still considered controversial by some. One reason may be that various reported series include patients with widely varying prognostic variables. To address this, the effect of chemotherapy on the continuous disease-free (CNED) survival was analyzed in 100 patients aged 21 yr or less with OSA of the femur. This classically poor prognostic group of patients represented 51% of all primary OSA seen at the Memorial Sloan-Kettering Cancer Center during the study interval. This study includes all patients aged 21 yr or less with fully malignant (Grade III-IV/IV) OSA of the femur and no metastases treated from November 1973 through November 1981. The first (T-4) protocol (31 patients) consisted of high dose methotrexate (HDMTX) with leucovorin rescue, cyclophosphamide (Cyc), and adriamycin. In the second (T-7) protocol (23 patients) the dose of HDMTX was increased to 12 g/m2 for prepubescent patients, and bleomycin, Cyc, and dactinomycin replaced Cyc. The current (T-10) protocol (46 patients) uses the same CT as T-7, but patients not having a complete response of the primary tumor to preoperative CT receive additional cisplatinum (120 mg/m2) with adriamycin (30 mg/m2/day for two consecutive days). In 31 patients treated with T-4 the CNED survival was 32% with a minimum follow up of over 7 yr. On T-7, 15/23 patients with femur primaries had a CNED survival of 65% with all of the surviving patients followed for more than 5 yr. The addition of cisplatinum in T-10 has resulted in CNED survival rate of 77% in 34/44 patients (excluding two patients that died CNED during and after treatment); the median follow-up patients who are alive CNED is 33 months, with a minimum of 2 yr follow up on the last patient entered.

Adolescent↗
PubMed1984

Harrington rod stabilization for pathological fractures of the spine.

Nineteen patients with tumors involving the thoracolumbar spine were treated by Harrington rod stabilization following laminectomy. Sixteen patients had metastatic neoplasms, and three had primary tumors of the vertebral column. In five patients, extensive decompressive laminectomy and Harrington distraction rods to provide immediate stability were used as initial treatment; postoperative irradiation was then given. All five patients were ambulatory, and the four patients with preoperative pain all noted relief of pain following treatment. The remaining 14 patients had received radiation therapy to the spine prior to surgery; in these 14, indications for surgery included a combination of pain and weakness (10 patients), pain alone (two patients), or weakness alone (two patients). Of 12 patients with preoperative pain, after surgery pain relief was noted in nine patients, and eight were ambulatory. Major wound breakdowns occurred in two of the 14 patients who had received radiation prior to surgery. These results suggest that Harrington rod instrumentation is useful in providing postoperative stability and restoring alignment following laminectomy for tumors involving the spine, but carries an increased risk of wound-related complications if used in a previously irradiated region.

Adolescent↗
PubMed1984

Osteoporosis.

Osteoporosis is a skeletal condition in which there is a loss of bone mass, evident radiographically by diffuse rarefaction or clinically by overt fractures. It is a widespread disorder of the elderly. Several forms of osteopenia, including osteomalacia, endocrinopathy, and marrow disorders, simulate osteoporosis. In this article, there is a discussion of the risk factors in the development of osteoporosis, as well as the pathophysiology, clinical presentation, diagnosis, and treatment of the condition, including combination therapy with calcium, vitamin D, and sodium fluoride.

Calcium↗
PubMed1984

Current concepts of Paget's disease of bone.

Paget's disease of bone is a process of increased bone remodeling resulting in architecturally abnormal bone that may affect any area of the skeleton. Paget's disease may present with a wide variation in the clinical and radiographic picture. When symptoms arise, they depend on the site and the extent of skeletal involvement. The two major therapeutic agents available for medical treatment are calcitonin and diphosphonate. Surgical intervention in Paget's disease is indicated for (1) selected fractures, (2) severe disabling arthritis, and (3) extreme bowing deformities causing malalignment of weight-bearing joints.

Arthritis↗
PubMed1984

Mineral parameters in early fracture repair.

In an effort to define and characterize the initial mineralization product of fracture-healing, we studied the mineral components within a model of endochondral osseous repair. Fracture calluses from the tibiae of rats and rabbits undergoing endochondral fracture-healing were analyzed, in toto and following density fractionation, by physicochemical and crystallographic techniques. Significant changes in mineral composition, crystal size, and density occurred in the early phases of fracture repair. In the rat, two weeks after fracture, the calcium-to-phosphorus ratio was higher than that of the mineral component, possibly due to calcium-binding to some of the macromolecules known to be present. The earliest mineral was poorly crystallized hydroxyapatite with a high carbonate content. Crystal perfection improved rapidly and approached that of normal diaphyseal bone within eight weeks after endochondral fracture in both the rabbit and the rat.

Animals↗
PubMed1984

The healing of segmental bone defects induced by demineralized bone matrix. A radiographic and biomechanical study.

UNLABELLED: We studied the effect of demineralized bone matrix on the repair of large femoral diaphyseal defects in a rat model by clinical, radiographic, and biomechanical methods. A standard procedure was first developed to create segmental defects that did not heal and in which non-union developed consistently. The effect of demineralized bone matrix on repair was then assessed by physical examination, serial radiographs, and biomechanical studies to determine deformation to failure, stiffness, torsional strength, and energy absorption. By twelve weeks, the defects that had been treated with demineralized bone matrix showed satisfactory repair and remodeling in most animals based on clinical and radiographic evaluation. The biomechanical studies demonstrated that the bone induced by demineralized bone matrix had an energy-absorption capacity and stiffness equal to those of intact rat femoral bone. The bone induced by demineralized bone matrix achieved 35 per cent of the torsional strength of normal bone and an increased capacity to deform under load. These biomechanical properties are similar to those observed in the early stages of normal fracture repair. CLINICAL RELEVANCE: An effective, readily available alternative to autologous bone-graft material would have a variety of clinical uses in orthopaedic surgery, such as augmenting fusions, aiding in the repair of high-risk fractures, and filling or bridging bone defects. Demineralized bone matrix may provide an important tool for these purposes by inducing bone that has the mechanical properties of fracture callus. This would reduce the morbidity associated with harvesting autologous bone and have an advantage over allografts or synthetic biomaterials that require incorporation by the host before they can support mechanical loads.

Animals↗